Welcome to YorkieTalk! I always kept food down for Sophie when she was small and I think she ate up to 1/4 cup per day but it's been awhile. Since your yorkie is so young be sure you have Nutrical handy for a sugar boost if needed to guard against hypoglycemia. Karo syrup will work, too.
Your breeder, vet or even your puppy kibble bag should have feeding amount per age available for you. Be sure your puppy gets lots of nap time as they wear out quickly from playing.
What's your puppy's name. Post a photo when you can
!